Annabel, a human, had a daughter named Gerbera. Gerbera lives in a mansion surrounded by marigold flowers and is called the “Monster by the Window” by the whole town because she is a “dhampir,” a mixed race of human and vampire. Annabel is a novelist who, under the pseudonym “Dali Delico,” has gained popularity for her work on the lore of the TRUMP, a vampire with eternal life. She chooses as her next subject as the “disappearance of youths in the Cocoon period,” which is being quietly talked about in the world of vampires. At this time, Annabel meets two boys, Sophie and Ul, who claim to be her biggest fans.